Clarifying the longitudinal factor structure, temporal stability, and construct validity of Go/No-Go task-related neural activation across adolescence and young adulthood

This study aimed to clarify the psychometric properties and development of Go/No-Go (GNG) task-related neural activation across critical periods of neurobiological maturation by examining its longitudinal stability, factor structure, developmental change, and associations with a computational index of task-general cognitive control. A longitudinal sample (N=289) of adolescents from the Michigan Longitudinal Study was assessed at four time-points (mean number of timepoints per participant=2.05; standard deviation=0.89) spanning early adolescence (ages 10-13) to young adulthood (22-25). Results suggested that regional neural activations from the "successful inhibition" (SI>GO) and "failed inhibition" (FI>GO; error-monitoring) contrasts are each described well by a single general factor. Neural activity across both contrasts showed developmental increases throughout adolescence that plateau in young adulthood. Neural activity metrics evidenced low temporal stability across this period of marked developmental change, and the SI>GO factor showed no relations with a behavioral index of cognitive control. The FI>GO factor displayed stronger criterion validity in the form of significant, positive associations with behaviorally measured cognitive control. Findings emphasize the utility of well-validated psychometric methods and longitudinal data for clarifying the measurement properties of functional neuroimaging metrics and improving measurement practices in developmental cognitive neuroscience.

Error-related brain activity associated with obsessive-compulsive symptoms in youth

BACKGROUND

Subclinical obsessive-compulsive symptoms (OCS) are common in children, and increase risk for later onset of obsessive-compulsive disorder (OCD). In pediatric patients with OCD, neuroimaging research implicates altered neural mechanisms for error-processing, but whether abnormal brain response occurs with subclinical OCS remains poorly understood.

METHODS

Using functional magnetic resonance imaging (fMRI), 113 youth (8-18 years; 45 female) from a community sample were scanned during an error-eliciting Go/No-Go task. OCS were assessed dimensionally using the obsessive-compulsive subscale of the Child Behavior Checklist. The association between OCS scores and error-related brain activity was examined at the whole-brain level.

RESULTS

Lower OCS scores associated with stronger response to errors in dorsal anterior cingulate cortex (dACC), caudate, putamen, thalamus, and occipital cortex. Additionally, lower OCS related to higher capacity for inhibitory control, as indexed by greater accuracy on No-Go trials during fMRI scanning. The relationship between lower OCS and better accuracy on No-Go trials was mediated by greater error-related dACC activity.

CONCLUSIONS

The inverse relationship between OCS and error-related activity in the dACC and extended cortical-striatal-thalamic circuitry may index an adaptive process by which subclinical OCS are minimized in youth. Further, these results identify an observable pattern of brain activity that tracks with subclinical OCS severity. Understanding the link between neural networks for error processing and the normal to abnormal range of OCS may pave the way for brain-based strategies to identify children who are more likely to develop OCD and enable the targeting of preventive strategies to reduce risk.

Nucleus Accumbens Response to Reward among Children with a Family History of Alcohol Use Problems: Convergent Findings from the ABCD Study® and Michigan Longitudinal Study

Having a family history of alcohol use problems (FH+) conveys risk for alcohol use in offspring. Reward-related brain functioning may play a role in this vulnerability. The present study investigated brain function in the nucleus accumbens (NAcc) associated with the anticipation of reward in youth with two biological parents with alcohol use problems (FH+2), one biological parent with alcohol use problems (FH+1), and no biological parents with alcohol use problems (FH-). Participants were from the large, national Adolescent Brain Cognitive Development (ABCD) Study (mean age: 9.93; 48% female; FH+2 n = 223, FH+1 n = 1447, FH- n = 9690) and the Michigan Longitudinal Study (MLS), consisting of community-recruited families with high rates of alcohol use disorder (mean age: 10.54; 39.3% female; FH+2 n = 40, FH+1 n = 51, FH- n = 40). Reward anticipation was measured by the monetary incentive delay task. Regression models were used to assess associations between FH status and the anticipation of large rewards in right and left NAcc regions of interest. In both studies, FH+2 youth showed blunted anticipatory reward responding in the right NAcc compared to FH+1 youth. In the MLS, FH+2 youth also had blunted anticipatory reward responding in the right NAcc compared to the FH- group. Convergent results across two separate samples provide insights into a unique vulnerability of FH+2 youth and suggest that binary FH+ versus FH- categorizations may obscure important differences within FH+ youth.

Sex Moderates Reward- and Loss-Related Neural Correlates of Triarchic-Model Traits and Antisocial Behavior

Abnormalities in responses to reward and loss are implicated in the etiology of antisocial behavior and psychopathic traits. While there is evidence for sex differences in neural response to reward and loss, it remains unclear how sex differences may moderate links between these neural responses and the phenotypic expression of antisocial behavior and psychopathic traits. This study examined sex differences in associations of neural response to reward and loss with antisocial personality symptoms and psychopathic traits. Functional neuroimaging data were collected during a monetary incentive delay task from 158 participants. Among males, during loss anticipation, activation in the left nucleus accumbens was negatively associated with antisocial behavior. Among females, during loss feedback, activation in the left nucleus accumbens and left amygdala was negatively associated with antisocial behavior. These results suggest that phenotypic sex differences in psychopathic traits and antisocial behavior may in part be attributable to different etiological pathways.

Evidence accumulation and associated error-related brain activity as computationally-informed prospective predictors of substance use in emerging adulthood

RATIONALE

Substance use peaks during the developmental period known as emerging adulthood (ages 18-25), but not every individual who uses substances during this period engages in frequent or problematic use. Although individual differences in neurocognition appear to predict use severity, mechanistic neurocognitive risk factors with clear links to both behavior and neural circuitry have yet to be identified. Here, we aim to do so with an approach rooted in computational psychiatry, an emerging field in which formal models are used to identify candidate biobehavioral dimensions that confer risk for psychopathology.

OBJECTIVES

We test whether lower efficiency of evidence accumulation (EEA), a computationally characterized individual difference variable that drives performance on the go/no-go and other neurocognitive tasks, is a risk factor for substance use in emerging adults.

METHODS AND RESULTS

In an fMRI substudy within a sociobehavioral longitudinal study (n = 106), we find that lower EEA and reductions in a robust neural-level correlate of EEA (error-related activations in salience network structures) measured at ages 18-21 are both prospectively related to greater substance use during ages 22-26, even after adjusting for other well-known risk factors. Results from Bayesian model comparisons corroborated inferences from conventional hypothesis testing and provided evidence that both EEA and its neuroimaging correlates contain unique predictive information about substance use involvement.

CONCLUSIONS

These findings highlight EEA as a computationally characterized neurocognitive risk factor for substance use during a critical developmental period, with clear links to both neuroimaging measures and well-established formal theories of brain function.

Heterogeneity Within Youth With Childhood-Onset Conduct Disorder in the ABCD Study

The purpose of this study was to examine if personality traits can be used to characterize subgroups of youth diagnosed with childhood-onset conduct disorder (CD). Participants were 11,552 youth from the Adolescent Brain Cognitive Development study. Data used in this report came from doi: 10.15154/1504041 (M age 9.92; 45.3% female, 49.6% white, 19.0% Hispanic). A subset of this sample (n = 365) met criteria for CD. Latent profile analyses (LPA) were performed on this subgroup (n = 365) to define profiles of individuals with CD based on self-report measures of impulsivity, punishment sensitivity, reward response, and callous-unemotional traits. Follow up analyses determined if these groups differed on clinically relevant variables including psychopathology, environmental risk factors, social risk factors, and neurocognitive functioning. Participants with a CD diagnosis scored significantly higher on psychological, environmental, social, and neurocognitive risk factors. The LPA revealed three unique profiles, which differed significantly on liability for broad psychopathology and domain-specific liability for externalizing psychopathology but were largely matched on environmental and social risk factors. These unique configurations provide a useful way to further parse clinically relevant subgroups within youth who meet criteria for childhood-onset CD, setting the stage for prospective longitudinal research using these latent profiles to better understand the development of youth with childhood-onset CD.

Developmental maturation of inhibitory control circuitry in a high-risk sample: A longitudinal fMRI study

Background

The goal of this work was to characterize the maturation of inhibitory control brain function from childhood to early adulthood using longitudinal data collected in two cohorts.

Methods

Functional MRI during a go/no-go task was conducted in 290 participants, with 88 % undergoing repeated scanning at 1- to 2-year intervals. One group entered the study at age 7–13 years (n = 117); the other entered at age 18–23 years (n = 173). 33.1 % of the sample had two parents with a substance use disorder (SUD), 43.8 % had one parent with an SUD, and 23.1 % had no parents with an SUD. 1162 scans were completed, covering ages 7–28, with longitudinal data from the cohorts overlapping across ages 16–21. A marginal model with sandwich estimator standard errors was used to characterize voxel-wise age-related changes in hemodynamic response associated with successful inhibitory control.

Results

There was significant positive linear activation associated with age in the frontal, temporal, parietal, and occipital cortices. No clusters survived thresholding with negative linear, positive or negative quadratic, or positive or negative cubic contrasts.

Conclusions

These findings extend previous cross-sectional and small-scale longitudinal studies that have observed positive linear developmental trajectories of brain function during inhibitory control.

The role of pubertal timing in the link between family history of alcohol use disorder and late adolescent substance use

BACKGROUND

Youth who experience puberty earlier than their peers are at heightened risk for substance use during adolescence. However, little is known about whether pubertal timing exacerbates effects of relevant early risk factors, such as family substance use history, as predicted by the "accentuation hypothesis". Using longitudinal data from youth with and without a family history of alcohol use disorder (AUD FHx), we evaluated whether pubertal timing intensifies preexisting familial risk effects on late adolescent substance use.

METHODS

Participants were 568 males and 245 females from the Michigan Longitudinal Study. Pubertal timing was indexed by fitting mixed-effects linear models to repeated measures of self-reported Tanner stage. Multilevel models then tested: (a) whether AUD FHx predicted pubertal timing, and (b) whether AUD FHx, pubertal timing, or their interaction predicted alcohol and marijuana use at ages 16-18.

RESULTS

AUD FHx was unrelated to pubertal timing in either males or females. In males, alcohol and marijuana use in late adolescence were predicted by AUD FHx and timing, but not their interaction. In females, AUD FHx predicted alcohol-related outcomes, but there were no main or interaction effects of timing.

CONCLUSIONS

Pubertal timing does not moderate the link between AUD FHx and late adolescent substance use, in contrast to the accentuation hypothesis. In males, measures of pubertal maturation and familial risk provide unique information for prediction of use. Females displayed no link between pubertal timing and use, which may suggest different risk pathways, or may have been due to the female sample's smaller size.

Alcohol expectancies mediate the association between the neural response to emotional words and alcohol consumption

BACKGROUND

Both positive expectancies regarding the effects of alcohol and internalizing problems, including negative emotionality and deficits in emotion regulation, are known risk factors for alcohol use disorder (AUD). The current study is the first to investigate how neural response to emotional stimuli may impact alcohol expectancies and risk for AUD.

METHODS

Functional neuroimaging data was collected during an emotional word task from 168 emerging adults (M age = 19.65; 66% male). Activation to negative versus neutral words and positive versus neutral words was extracted for analyses. Participants also reported on their alcohol expectancies and information regarding alcohol use and problems was collected prospectively throughout adolescence and into adulthood (up to age 30).

RESULTS

Decreased activation in the inferior frontal gyrus (IFG) to negative versus neutral words was associated with increased post-scan alcohol consumption, measured as average drinks per year. There was a significant indirect effect of positive alcohol expectancies on the association between IFG activation and post-scan alcohol consumption, even when controlling for quantity of alcohol consumption prior to the scan.

CONCLUSIONS

These results are the first to provide evidence that positive alcohol expectancies account for variance shared between brain regions associated with emotion processing and increased drinking behaviors. Alcohol expectancies may provide a modifiable target for treatments to decrease the link between deficits in emotion regulation and increased alcohol use.

Neural correlates of inhibitory control in youth with symptoms of food addiction

Prior research has found that food addiction is associated with reward-related neural differences, but research has yet to examine whether there are also neural differences in inhibitory control. This may be particularly relevant during adolescence as it is a key developmental period where difficulties in inhibitory control are more prevalent. The Yale Food Addiction Scale is a self-report questionnaire that applies substance use disorder diagnostic criteria to certain foods that has also been adapted for children. Here we investigate the association between addictive-like eating and brain functioning during inhibitory control in youth. Seventy-six right-handed participants 8.2-17.8 years (44 male) were recruited. Participants performed a go/no-go task during functional magnetic resonance imaging and completed the Yale Food Addiction Scale for Children, after which they were categorized into two groups according to their scores (No Symptom Group = 0; YFAS-C Group: score ≥ 1). Inhibitory control was probed with a contrast of correct no-go versus go trials. An independent-samples t-test comparing groups revealed a significant difference in three primary clusters, all exclusively in the left hemisphere (No Symptom Group > YFAS-C Group): middle temporal gyrus/occipital gyrus, precuneus/calcarine sulcus, and inferior frontal gyrus. Specifically, the YFAS-C Group showed deactivation in all three clusters. Adolescents who endorse food addiction appear to show hypo-activation in response to the inhibitory control portion of a go/no-go task, which suggests possible inhibitory control difficulties.

Frontostriatal Resting State Functional Connectivity in Resilient and Non-Resilient Adolescents with a Family History of Alcohol Use Disorder

Objectives: Youth with parental substance use disorder (family-history positive [FH+]) are at an elevated risk for substance use problems, but not all FH+ youth experience this outcome. Frontostriatal brain networks involved in inhibitory control and reward responsivity underlie risk-taking behaviors, but the role of these networks in substance use heterogeneity among FH+ youth has not been examined. The present study examined resting state functional connectivity (RSFC) in frontostriatal networks in FH+ youth with and without risky substance use. Methods: Participants were 36 FH+ adolescents (mean age 14.96 years at the scan date; 36% female) from a longitudinal, community-based functional magnetic resonance imaging study enriched for parental alcohol use disorder. Groups were based on the absence (resilient) or presence (high-risk) of at least one occasion of any substance use by age 14 and also use of at least two different types of substances by the most recent substance use assessment (mean age 16.89 years). Bilateral masks of the dorsolateral prefrontal cortex (DLPFC) and the nucleus accumbens were used for seed-based RSFC due to the importance of these regions in executive control and salience networks, respectively. Results: Compared with FH+/high-risk youth, FH+/resilient youth displayed greater connectivity between the left DLPFC seed and the left posterior cingulate cortex. No other brain regions showed significantly different RSFC between resilient and high-risk groups. Conclusion: FH+/resilient youth showed stronger synchrony between brain regions associated with cognitive control, particularly those associated with flexible adaptation of thoughts and behaviors. Although preliminary, the results of this study set the stage for a continued focus on risk-group heterogeneity to better identify neural markers of resilience against substance use problems in vulnerable populations.

Review of Neurobiological Influences on Externalizing and Internalizing Pathways to Alcohol Use Disorder

Purpose of review

Two developmental courses through which alcohol use disorder (AUD) may emerge include externalizing and internalizing pathways. We review recent neuroimaging studies of potential neural risk factors for AUD and link findings to potential behavioral risk factors for AUD.

Recent findings

There is evidence that early-emerging weakness in prefrontal functioning and later-emerging differences in reward-system functioning contribute to an externalizing risk pathway. Stress may be an important contributor in the internalizing pathway through a blunting of reward-related activation, which may act alone or in combination with heightened emotion-related reactivity.

Summary

This review highlights areas for future work, including investigation of the relative balance between prefrontal and subcortical circuitry, attention to stages of AUD, and consideration of environmental factors such as stress and sleep. Particularly important is longitudinal work to understand the temporal ordering of associations among brain maturation, behavioral risk, and alcohol use.

Sex Differences in the Developmental Neuroscience of Adolescent Substance Use Risk

Adolescence is a period associated with the initiation and escalation of substance use and is also a time during which substantial changes take place in neural development, personality and behavior. Although rates of substance use between adolescent girls and boys do not differ substantially, there is evidence for sex differences in underlying vulnerability pathways associated with the development of substance use disorder. Here we review sex differences in adolescent brain development and how these differences may contribute to different risk pathways between females and males that emerge during this developmental period. We also discuss methodological considerations in the study of sex differences in brain and behavior and their implications for interpretation. We close by highlighting promising areas for future work.

Sex differences in the development of emotion circuitry in adolescents at risk for substance abuse: a longitudinal fMRI study

There is substantial evidence for behavioral sex differences in risk trajectories for alcohol and substance use, with internalizing factors such as negative affectivity contributing more to female risk. Because the neural development of emotion circuitry varies between males and females across adolescence, it represents a potential mechanism by which underlying neurobiology contributes to risk for substance use. Longitudinal functional magnetic resonance imaging was conducted in males and females (n = 18 each) with a family history of alcohol use disorders starting at ages 8-13 years. Participants performed an affective word task during functional magnetic resonance imaging at 1- to 2-year intervals, covering the age range of 8.5-17.6 years (3-4 scans per participant). Significant age-related sex differences were found in the right amygdala and right precentral gyrus for the negative vs neutral word condition. Males showed a significant decrease in both amygdala and precentral gyrus activation with age, whereas the response in females persisted. The subjective experience of internalizing symptomatology significantly increased with age for females but not for males. Taken together, these results reveal sex differences in negative affect processing in at-risk adolescents, and offer longitudinal neural evidence for female substance use risk through internalizing pathways.

Effects of the serotonin transporter gene, sensitivity of response to alcohol, and parental monitoring on risk for problem alcohol use

The serotonin transporter-linked polymorphic region (5-HTTLPR) of the serotonin transporter gene (SLC6A4) has been previously associated with alcohol-related risk. Most findings point to short (S) allele carriers being at increased risk for negative alcohol outcomes relative to long allele homozygotes, although some work indicates a more complex relationship. The current prospective study aimed to clarify how and under what circumstances variations in 5-HTTLPR transmit risk for various alcohol-related outcomes. Participants were 218 adolescents and young adults (29% female) enrolled in the Michigan Longitudinal Study. We tested a moderated mediation model with 5-HTTLPR as the predictor, Self-Rating of the Effects of Alcohol (SRE) score as the mediator, alcohol-related outcomes as the dependent variables, parental monitoring as the moderator of the SRE to alcohol outcomes path, and prior drinks, sex, age, and body mass index as covariates. Four alcohol-related outcomes were tested. The S allele was associated with higher SRE scores (i.e., lower response to alcohol). Parental monitoring was a significant moderator: At low levels of parental monitoring, higher SRE scores predicted more drinks consumed and binge drinking episodes. At high levels of monitoring, higher SRE scores were significantly related to fewer alcohol-related problems. Findings suggest that one mechanism by which 5-HTTLPR variation transmits alcohol-related risk is through level of response to alcohol. Furthermore, the strength and direction of this effect varied by level of parental monitoring, indicating that even in the presence of genetic and physiological vulnerability, parents can influence the likelihood of offspring developing problematic alcohol-related behaviors.

Reduced brain activation during inhibitory control in children with COMT Val/Val genotype

INTRODUCTION

Behavioral undercontrol is a well-established risk factor for substance use disorder, identifiable at an early age well before the onset of substance use. However, the biological mechanistic structure underlying the behavioral undercontrol/substance use relationship is not well understood. The enzyme catechol O-methyltransferase (COMT) catabolizes dopamine and norepinephrine in the prefrontal cortex and striatum, brain regions involved in behavioral control. The goal of this work was to investigate the association between genetic variation in COMT functioning and fronto-striatal brain functioning during successful inhibitory control, a critical aspect of behavioral control.

METHODS

Participants were 65 (22 female) 7-12 year olds who were genotyped for the functional COMT Val¹⁵⁸Met (rs4680) single-nucleotide polymorphism and underwent functional magnetic resonance imaging while performing a go/no-go task. The majority of the sample (80%) had at least one parent with a history of alcohol use disorder and were thus at heightened risk for substance use disorders.

RESULTS

There was a significant main effect of genotype on brain activation in left and right putamen during successful versus failed inhibition and in right inferior frontal gyrus/insula during successful inhibition versus baseline. Follow-up tests revealed that Met homozygotes had greater activation in each region relative to Val homozygotes.

CONCLUSIONS

These results are relevant for understanding how specific genes influence brain functioning related to underlying risk factors for substance use disorders and other disinhibitory psychopathologies.

Association of Marijuana Use With Blunted Nucleus Accumbens Response to Reward Anticipation

IMPORTANCE

Marijuana use may alter ventral striatal response to reward, which might heighten susceptibility to substance use disorder. Longitudinal research is needed to determine the effects of marijuana use on neural function involved in reward response.

OBJECTIVE

To determine whether marijuana use among young adults prospectively affects nucleus accumbens (NAcc) activation during reward anticipation.

DESIGN, SETTING, AND PARTICIPANTS

One hundred eight young adults were recruited from the Michigan Longitudinal Study, an ongoing study of youth at high risk for substance use disorder and a contrast sample of control families. Participants underwent 3 consecutive functional magnetic resonance imaging scans at approximate ages of 20 (time 1), 22 (time 2), and 24 (time 3) years. Self-report data on marijuana and other drug use occasions were collected annually since age 11 years.

MAIN OUTCOMES AND MEASURES

Cross-lagged models were used to test the association of marijuana use with neural response in the NAcc to reward anticipation during a monetary incentive delay task controlling for sex, age, other substance use, and family history of substance use disorder.

RESULTS

Of 108 participants, 39 (36.1%) were female and mean (SD) age at baseline was 20.1 (1.4) years. Greater marijuana use was associated with later blunted activation in the NAcc during reward anticipation (time 1 to time 2: β = -0.26, P = .04; time 2 to time 3: β = -0.25, P = .01). When the cross-lagged model was tested with the inclusion of previous and concurrent cigarette use, the effect of marijuana use from time 2 to time 3 remained significant (β = -0.29; P = .005) and the effect of cigarette use was nonsignificant.

CONCLUSIONS AND RELEVANCE

The findings of this study indicate that marijuana use is associated with decreased neural response in the NAcc during the anticipation of nondrug rewards. Over time, marijuana use may alter anticipatory reward processing in the NAcc, which may increase the risk for continued drug use and later addiction.

Brain activation to negative stimuli mediates a relationship between adolescent marijuana use and later emotional functioning

This work investigated the impact of heavy marijuana use during adolescence on emotional functioning, as well as the brain functional mediators of this effect. Participants (n=40) were recruited from the Michigan Longitudinal Study (MLS). Data on marijuana use were collected prospectively beginning in childhood as part of the MLS. Participants were classified as heavy marijuana users (n=20) or controls with minimal marijuana use. Two facets of emotional functioning-negative emotionality and resiliency (a self-regulatory mechanism)-were assessed as part of the MLS at three time points: mean age 13.4, mean age 19.6, and mean age 23.1. Functional neuroimaging data during an emotion-arousal word task were collected at mean age 20.2. Negative emotionality decreased and resiliency increased across the three time points in controls but not heavy marijuana users. Compared with controls, heavy marijuana users had less activation to negative words in temporal, prefrontal, and occipital cortices, insula, and amygdala. Activation of dorsolateral prefrontal cortex to negative words mediated an association between marijuana group and later negative emotionality. Activation of the cuneus/lingual gyrus mediated an association between marijuana group and later resiliency. Results support growing evidence that heavy marijuana use during adolescence affects later emotional outcomes.

Neuroimaging Risk Markers for Substance Abuse: Recent Findings on Inhibitory Control and Reward System Functioning

Rates of alcohol and other drug use rise sharply throughout adolescence and peak in the early 20s. Likewise, prevalence of first-time substance use disorder (SUD) and past-year SUD both peak between ages 18-23. SUD is associated with a host of negative outcomes and is a serious health concern. Understanding the mechanisms that precede the onset and escalation of substance use is crucial in order to develop more effective prevention and intervention strategies for children and adolescents at risk for SUD. In this review, we discuss recent findings from functional neuroimaging studies in children, adolescents, and emerging adults that focus on uncovering the neural underpinnings of SUD risk. The focus is on inhibitory control and reward circuitry due to their involvement in risk-taking behaviors, which are heightened in adolescence and may facilitate substance use. We discuss convergences in the literature and highlight findings suggesting that the association between SUD risk and neurofunctioning may be moderated by age, gender, and history of substance use. Recommendations for future directions are also discussed.

Development of impulse control circuitry in children of alcoholics

BACKGROUND

Difficulty with impulse control is heightened in children with a family history of alcohol use disorders and is a risk factor for later substance problems. Cross-sectional functional magnetic resonance imaging studies have shown altered impulse control processing in adolescents with a positive family history, yet developmental trajectories have yet to be examined.

METHODS

Longitudinal functional magnetic resonance imaging was conducted in children of alcoholic families (family history positive [FH+]; n = 43) and children of control families (family history negative [FH-]; n = 30) starting at ages 7-12 years. Participants performed a go/no-go task during functional magnetic resonance imaging at intervals of 1-2 years, with two to four scans performed per subject. We implemented a repeated-measures linear model fit across all subjects to conduct a whole-brain search for developmental differences between groups.

RESULTS

Performance improved with age in both groups, and there were no performance differences between groups. Significant between-group differences in linear age-related activation changes were found in the right caudate, middle cingulate, and middle frontal gyrus. Post hoc analyses revealed significant activation decreases with age in the caudate and middle frontal gyrus for FH- subjects and a significant increase with age in middle cingulate activation for FH+ subjects. Group differences were evident at age 7-12 years, even in alcohol- and drug-naïve participants, with FH+ subjects showing significantly blunted activation at baseline compared with FH- subjects.

CONCLUSIONS

Differences in response inhibition circuitry are visible in FH+ individuals during childhood; these differences continue into adolescence, displaying trajectories that are inconsistent with development of normal response inhibition. These patterns precede problem drinking and may be a contributing factor for subsequent substance use problems.

Left middle frontal gyrus response to inhibitory errors in children prospectively predicts early problem substance use

BACKGROUND

A core vulnerability trait for substance use disorder (SUD) is behavioral disinhibition. Error processing is a central aspect of inhibitory control that determines adaptive adjustment of performance; yet it is a largely overlooked aspect of disinhibition as it relates to risk for SUD. We investigated whether differences in brain activation during both successful and failed inhibition predicts early problem substance use.

METHOD

Forty-five 9-12 year olds underwent a functional MRI scan during a go/no-go task. They were then followed over approximately 4 years, completing assessments of substance use. Externalizing behavior was measured at ages 3-8, 9-12 and 11-13. Participants with drug use or problem alcohol use by ages 13-16 (n=13; problem-user group) were individually matched by gender, age, and family history of alcoholism with non-substance-using children (n=13; non-user group). The remaining 19 participants provided an independent sample from which to generate unbiased regions-of-interest for hypothesis testing in the problem-user and non-user groups.

RESULTS

No differences were observed between groups in activation during correct inhibition compared with baseline. A significant difference arose in left middle frontal gyrus (LMFG) activation during failed inhibition compared with correct inhibition, with the problem-user group demonstrating blunted activation. The problem-user group also had more externalizing problems at ages 11-13. Logistic regression found that activation of LMFG significantly predicted group membership over and above externalizing problems.

CONCLUSIONS

Blunted LMFG activation during performance errors may underlie problems adapting behavior appropriately, leading to undercontrolled behavior, early problem substance use and increased risk for SUD.

Representation of response alternatives in human presupplementary motor area: multi-voxel pattern analysis in a go/no-go task

A debate exists as to the role of the presupplementary motor area (preSMA) in cognitive control. Recent findings suggest that preSMA plays a central role in conflict resolution and encodes response alternatives as opposed to simply the presence of conflict. Evidence of neuronal heterogeneity within preSMA of non-human primates suggests that univariate analysis of functional MRI data may not provide adequate resolution to fully characterize cognitive control-related responses. Here, multi-voxel pattern analysis (MVPA) is employed to examine the distributed patterns of activity in preSMA associated with both successful go responses and no-go inhibitions. In a go/no-go task, univariate analysis showed undifferentiated activation of preSMA in response to both go and no-go stimuli. However, when an anatomically-defined preSMA ROI was subjected to MVPA, a significant difference in the activation pattern encoded by go as compared to no-go stimuli was observed. These differences in preSMA activation are consistent with the ongoing maintenance and manipulation of stimulus-action representations.

Patterns of neural connectivity during an attention bias task moderate associations between early childhood temperament and internalizing symptoms in young adulthood

BACKGROUND

Biased attention to threat is found in both individuals with anxiety symptoms and children with the childhood temperament of behavioral inhibition (BI). Although perturbed fronto-amygdala function is implicated in biased attention among anxious individuals, no work has examined the neural correlates of attention biases in BI. Work in this area might clarify underlying mechanisms for anxiety in a sample at risk for internalizing disorders. We examined the relations among early childhood BI, fronto-amygdala connectivity during an attention bias task in young adulthood, and internalizing symptoms, assessed in young adulthood.

METHODS

Children were assessed for BI at multiple age points from infancy through age seven. On the basis of a composite of observational and maternal report data, we selected 21 young adults classified as having a history of BI and 23 classified as non-BI for this study (n = 44). Participants completed an event-related functional magnetic resonance imaging attention-bias task involving threat (angry faces) and neutral trials. Internalizing symptoms were assessed by self-report and diagnostic interviews.

RESULTS

The young adults characterized in childhood with BI exhibited greater strength in threat-related connectivity than non-behaviorally inhibited young adults. Between-group differences manifested in connections between the amygdala and two frontal regions: dorsolateral prefrontal cortex and anterior insula. Amygdala-insula connectivity also interacted with childhood BI to predict young adult internalizing symptoms.

CONCLUSIONS

Behavioral inhibition during early childhood predicts differences as young adults in threat and attention-related fronto-amygdala connectivity. Connectivity strength, in turn, moderated the relations between early BI and later psychopathology.

DRD4 and striatal modulation of the link between childhood behavioral inhibition and adolescent anxiety

Behavioral inhibition (BI), a temperament characterized by vigilance to novelty, sensitivity to approach-withdrawal cues and social reticence in childhood, is associated with risk for anxiety in adolescence. Independent studies link reward hyper-responsivity to BI, adolescent anxiety and dopamine gene variants. This exploratory study extends these observations by examining the impact of DRD4 genotype and reward hyper-responsivity on the BI-anxiety link. Adolescents (N = 78) completed a monetary incentive delay task in the fMRI environment. Participants were characterized based on a continuous score of BI and the 7-repeat allele (7R+) of the DRD4 functional polymorphism. Parent-report and self-report measures of anxiety were also collected. Across the entire sample, striatal activation increased systematically with increases in the magnitude of anticipated monetary gains and losses. DRD4 status moderated the relation between BI and activation in the caudate nucleus. Childhood BI was associated with parent report of adolescent anxiety among 7R+ participants with elevated levels of striatal response to incentive cues. DRD4 genotype influenced the relations among neural response to incentives, early childhood BI and anxiety. The findings help refine our understanding of the role reward-related brain systems play in the emergence of anxiety in temperamentally at-risk individuals, building a foundation for future larger scale studies.

The left amygdala knows fear: laterality in the amygdala response to fearful eyes

The detection of threat is a role that the amygdala plays well, evidenced by its increased response to fearful faces in human neuroimaging studies. A critical element of the fearful face is an increase in eye white area (EWA), hypothesized to be a significant cue in activating the amygdala. However, another important social signal that can increase EWA is a lateral shift in gaze direction, which also serves to orient attention to potential threats. It is unknown how the amygdala differentiates between these increases in EWA and those that are specifically associated with fear. Using functional magnetic resonance imaging, we show that the left amygdala distinguished between fearful eyes and gaze shifts despite similar EWA increases whereas the right amygdala was less discriminatory. Additional analyses also revealed selective hemispheric response patterns in the left fusiform gyrus. Our data show clear hemispheric differences in EWA-based fear activation, suggesting the existence of parallel mechanisms that code for emotional face information.

Common and distinct brain activation to viewing dynamic sequences of face and hand movements

The superior temporal sulcus (STS) and surrounding lateral temporal and inferior parietal cortices are an important part of a network involved in the processing of biological movement. It is unclear whether the STS responds to the movement of different body parts uniformly, or if the response depends on the body part that is moving. Here we examined brain activity to recognizing sequences of face and hand movements as well as radial grating motion, controlling for differences in movement dynamics between stimuli. A region of the right posterior STS (pSTS) showed common activation to both face and hand motion, relative to radial grating motion, with no significant difference between responses to face and hand motion in this region. Distinct responses to face motion relative to hand motion were observed in the right mid-STS, while the right posterior inferior temporal sulcus (pITS) and inferior parietal lobule (IPL) showed greater responses to hand motion relative to face motion. These findings indicate that while there may be distinct processing of different body part motion in lateral temporal and inferior parietal cortices, the response of the pSTS is not body part specific. This region may provide input to other parts of a network involved with processing human actions with a high-level visual description of biological motion.